Preparation of konjac glucomannan based films reinforced with nanoparticles and its effect on cherry tomatoes preservation

Present study aims to investigate the effect of nanoparticles (zein nanoparticles, nanocellulose, nano-TiO2, nanoSiO(2)) incorporation on rheological properties of film-forming solutions and physicochemical properties of konjac glucomannan (KGM) based films, and to evaluate the effect of KGM/nanoparticles blend film on cherry tomatoes preservation. The results showed that the blend film-forming solutions exhibited shear-thinning behavior, and KGM/zein nanoparticle film-forming solution showed the lowest crossover frequency value of storage (G') and loss (G '') moduli due to enhanced molecular interaction and entanglement. The nanoparticles were dispersed homogeneously in the KGM continuous matrix and had good compatibility with KGM, thereby improving physicochemical properties of KGM based films. KGM/zein nanoparticle blend film (KNZ) showed the best properties, such as smoother surface and denser cross-section, the highest glass transition temperature and elongation at break, as well as the best moisture and oxygen barrier. In comparison with the control and polyethylene film packaging, cherry tomatoes in KNZ film packaging showed lower weight loss and firmness reduction, and had relatively stable content of total soluble solids, vitamin C content and pH value during storage up to 10 days at 26 degrees C. The results suggested the high potential of KNZ film for application in cherry tomatoes preservation.